read_instance

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=true, so the safety profile is covered. The description adds genuinely useful behavioral detail that no annotation carries: the return shape (with the AI Coach block being null when off) and the hedged accuracy caveat 'as far as leap can tell' for the openGym/compatibility fields. It does not cover auth requirements or failure behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

It is a single sentence, front-loaded with the instance state and then the configuration detail. The long parenthetical listing config keys is dense but every item earns its place given there is no output schema to carry them.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description takes on the job of describing the return payload and does so thoroughly, including the null-when-off coach block. It is slightly incomplete on scope (whose instance/config) and on any access requirements, but nothing essential for calling the tool is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool takes zero parameters, so per the rubric the baseline is 4. There is nothing for the description to clarify at the parameter level, and it correctly spends no words on inputs.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description enumerates exactly what the tool reports about the instance (up status, account count, openGym, write compatibility, and configuration keys), which makes the resource and scope unmistakable. It reads as a return-value listing rather than a verb-led statement of purpose, and it does not distinguish itself from adjacent readers like read_settings or read_account.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no statement of when to call this versus the many sibling readers (read_settings, read_account, read_me), nor any prerequisites such as required permissions. The agent must infer usage entirely from the field list.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.